PC boot looping?

I have an older PC now for the spare room, Asus Rampage IV Extreme, I7 3960X ETC that has just started boot looping (is the best way I can describe it) when I press the power button the fans spin up then down, couple of seconds and then same again, over and over, no time to get a signal to the monitor.

So far have tried to reset CMOS, also taken out the CMOS battery, still the same, will be trying a newer known good PSU next but thought I'd come on here for other idea's to try as well?

I've a feeling the PSU, a Corsair H1000 is/was the culprit here? was getting messages about power surge from the BIOS a couple of times before this happened, the PSU is getting on now, easily 7 years old at least and I really should have replaced it as assurance before now I know, its obviously well out of warranty, possibly the chance I've bricked the motherboard and possibly more? will know better when I get the chance to try my main PC's SuperFlower 1000 that is fairly knew.

Any other trouble shooting procedures to try before I look a\t it again?

Thanks.

You could try pulling each stick of ram on the off chance one of those has died

Thanks, will give that a go too.